[PATCH] ipmi: kcs: Poll OBF briefly to reduce OBE latency

Andrew Jeffery andrew at aj.id.au
Thu Oct 6 10:12:57 AEDT 2022

Hi Corey,

On Sat, 13 Aug 2022, at 00:17, Andrew Jeffery wrote:
> The ASPEED KCS devices don't provide a BMC-side interrupt for the host
> reading the output data register (ODR). The act of the host reading ODR
> clears the output buffer full (OBF) flag in the status register (STR),
> informing the BMC it can transmit a subsequent byte.
> On the BMC side the KCS client must enable the OBE event *and* perform a
> subsequent read of STR anyway to avoid races - the polling provides a
> window for the host to read ODR if data was freshly written while
> minimising BMC-side latency.

Just wondering whether you're happy to pick this one up? I haven't seen 
it hit the IPMI tree yet.



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